Gene and drug delivery systems are a very active field of scientific research and invention because of the significant needs for clinical applications of diagnosis and treatment and scientific research in vitro and in vivo as well as its limitations of currently available technologies. For example, poly(lactide-co-glycolide) (PLGA)-based nanoparticle has been developed for drug delivery; however, it has a very low efficiency to load and deliver nucleic acids such as DNA and RNA because of its chemical nature. Liposome and polyethylenimine (PEI) have been developed for delivering nucleic acid such as DNA and RNA in vitro and in vivo. However, efficiency of these delivery systems is limited; toxicity is also high; and preparation procedures are complicated. Currently, there are no delivery systems that have high efficacy and low toxicity in clinical applications. The present invention satisfies a long-felt need in the art for an efficient, low toxicity system to deliver at least one agent to an individual.